Recent breaks in clinical trials studying a potential coronavirus vaccine and therapeutic for safety reasons shouldn't be alarming for the American public, said Dr. Tom Frieden, former director of the Centers for Disease Control and Prevention, told CNBC on Tuesday.
Rather, Frieden said it was evidence that drug makers and regulators continued to adhere to the rigorous scientific principles that govern studies, even as they attempt to speed development times during the Covid-19 pandemic.
"It's kind of paradoxical, but actually comforting, because we expect signals that may not indicate a problem, and we expect companies to stop so they can look closely," said Frieden, who ran the CDC from 2009-2017 USA headed the Obama administration. "It gives you the certainty that we are not restricting security."
Peace's comments on Tuesday on "Closing Bell" followed news that a late-night study of Eli Lilly's antibody treatment for Covid-19 has been suspended by US regulators to allow potential safety concerns to be assessed.
Just a day earlier, Johnson & Johnson confirmed that the large-scale coronavirus vaccine study was interrupted when the safety watchdog panel investigated an "adverse event" in a participant. It is not yet known whether the person received the vaccine or a placebo.
UK pharmaceutical company AstraZeneca's vaccine trial continues to be on hold in the US after an unexplained disease was reported in a participant in the UK. However, regulators in the UK and other countries have allowed the trials to resume.
Medical experts say the pauses in vaccine and drug development trials are not uncommon, which usually takes years. But the recent safety freezes have gained increasing attention in the world amid a pandemic that killed more than 1 million people and devastated economies.
In the US, in particular, there were also growing concerns that the Trump administration might expedite approval of a coronavirus vaccine for political reasons. The head of the Food and Drug Administration, Dr. Stephen Hahn, has tried to allay those worries, saying he has "no intention" to override professional researchers at the agency.
Peace recognized confidence concerns about the vaccine, but the former New York health commissioner stressed that the public must wait for more information before reaching any conclusions. “People say, 'Would you take a vaccine?' If you asked me, I'd say, 'Well, it depends what the data shows,' he said. 'With time we will learn more. "